Disable steppers on M112 (#15065)

And change verbiage to not refer to "Emergency Stop."

Marlin/src/module/planner.h

@@ -715,8 +715,8 @@ class Planner {
       FORCE_INLINE static float get_axis_position_degrees(const AxisEnum axis) { return get_axis_position_mm(axis); }
     #endif
 
-    // Called to force a quick stop of the machine (for example, when an emergency
-    // stop is required, or when endstops are hit)
+    // Called to force a quick stop of the machine (for example, when
+    // a Full Shutdown is required, or when endstops are hit)
     static void quick_stop();
 
     // Called when an endstop is triggered. Causes the machine to stop inmediately